Fix miner AI issue

Author: someaddons

src/main/java/com/minecolonies/core/colony/workorders/AbstractWorkOrder.java

@@ -574,7 +574,7 @@ public void clearBlueprint()
     @Override
     public AABB getBoundingBox()
     {
-        if (box == Constants.EMPTY_AABB && colony.getWorld() != null)
+        if (box == Constants.EMPTY_AABB && colony != null && colony.getWorld() != null)
         {
             loadBlueprint(colony.getWorld(), b -> clearBlueprint());
         }

src/main/java/com/minecolonies/core/entity/ai/workers/production/EntityAIStructureMiner.java

@@ -780,7 +780,7 @@ private IAIState executeStructurePlacement(@NotNull final MineNode mineNode, @No
         mineNode.setStatus(MineNode.NodeStatus.IN_PROGRESS);
         building.markDirty();
         //Preload structures
-        if (job.getWorkOrder().getBlueprint() == null)
+        if (job.getWorkOrder() == null || job.getWorkOrder().getBlueprint() == null)
         {
             initStructure(mineNode,
               rotation,